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Why is SELECT * considered harmful?
...s more data to move from the database server to the client, slowing access and increasing load on your machines, as well as taking more time to travel across the network. This is especially true when someone adds new columns to underlying tables that didn't exist and weren't needed when the origina...
Good PHP ORM Library?
...ates everything on the fly)
No models
etc.
It even does all the locking and transactions for you and monitors performance in the background. (Heck! it even does garbage collection....) Best of all... you don't have to write a single... line of code... Jesus this, ORM layer, saved me ass!
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Convert PEM to PPK file format
...EM files to PPK files? (you may guess that Amazon EC2 gives me a PEM file, and I need to use the PPK format for SSH connectivity).
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Java generics - why is “extends T” allowed but not “implements T”?
...lass 'implements' or 'extends'. The constraint possibilities are 'extends' and 'super' - that is, is this class to operate with assignable to that other one (extends), or is this class assignable from that one (super).
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Linux equivalent of the Mac OS X “open” command [closed]
I've found the "open" command in Mac OS X very handy in the command line. From "man open":
7 Answers
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When to use thread pool in C#? [closed]
I have been trying to learn multi-threaded programming in C# and I am confused about when it is best to use a thread pool vs. create my own threads. One book recommends using a thread pool for small tasks only (whatever that means), but I can't seem to find any real guidelines. What are some consid...
What is the “volatile” keyword used for?
... correct usage. Could you please tell me what it should be used for in C# and in Java?
8 Answers
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Why does the arrow (->) operator in C exist?
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I'll interpret your question as two questions: 1) why -> even exists, and 2) why . does not automatically dereference the pointer. Answers to both questions have historical roots.
Why does -> even exist?
In one of the very first versions of C language (which I will refer as CRM for "C Refe...
HEAD and ORIG_HEAD in Git
What do these symbols refer to and what do they mean?
4 Answers
4
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How does a public key verify a signature?
...m trying to get a better grapple on how public/private keys work. I understand that a sender may add a digital signature to a document using his/her private key to essentially obtain a hash of the document, but what I do not understand is how the public key can be used to verify that signature.
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